JP3880740B2 - Displacement control device and actuator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention includes a displacement control device that is driven using a piezoelectric / electrostrictive element so that a part of the device draws a hysteresis-like displacement locus, and displacement and positioning adjustment of various precision parts such as optical equipment and precision equipment, The present invention relates to an actuator using the device that is suitably used as an angle adjustment mechanism, a rotary motor, a linear conveyance device, and the like.
[0002]
[Prior art]
In recent years, in the fields of optics, magnetic recording, precision processing, etc., displacement control elements and actuators that adjust the optical path length and position on the submicron order have been desired. Moreover, among micromachines that have been actively researched and developed in recent years by applying microfabrication technology, power components such as motors are device parts that can be used for extreme surgery in the medical field. Has attracted attention as.
[0003]
Furthermore, in various electronic devices that are rapidly becoming smaller and lighter, naturally used parts are downsized. Conveying machines and parts feeders used to transport and sort such parts However, there is a demand for a device that is suitable for the shape of the component and that can be driven with high accuracy.
[0004]
[Problems to be solved by the invention]
Conventionally, electromagnetic motors have been widely used as the actuators described above. However, the control accuracy by the electromagnetic motor is not so high. Therefore, for example, when used in a displacement control device, a configuration in which a large movement is performed by an electromagnetic motor and a smaller final movement (positioning) is performed using an element having another displacement mechanism may be used. Many. Further, the electromagnetic motor has a problem that power consumption is large.
[0005]
As a new technology to replace electromagnetic motors, for example, pages 1081 to 1084 of "1997 International Conference on solid-state Sensors and Actuators" of "TRANSDUCER '97" include electrostatics produced by a micromachine process of Si or Ni. A micro-actuator of the type has been introduced, in which a minute displacement can be obtained by applying a voltage between a plurality of plate-like electrodes formed by micromachining.
[0006]
However, in this actuator, it is difficult to increase the natural frequency because of the structure, and as a result, there is a problem that vibration is difficult to attenuate when operating at high speed, and the manufacturing cost of the process itself called micromachining is inherent. There is a problem in terms of. Therefore, the displacement control apparatus using such an actuator is also desired to be further improved in terms of driving accuracy and cost.
[0007]
[Means for Solving the Problems]
The present invention has been made in view of the problems of the various actuators described above, and an object of the present invention is to provide a displacement control device capable of high-speed and precise operation with low power and a plurality of the displacement control devices. It is to provide an actuator to be used.
[0008]
That is, according to the present invention, the coupling plate is sandwiched between the two diaphragms, and the coupling plate is joined to the bottom surface of the recess formed in the substrate, and the diaphragm is at least connected to the side surface of the recess. Not joined In addition, the thickness of the diaphragm is thinner than the thickness of each of the connecting plate and the substrate, and the diaphragm, the connecting plate, and the substrate are joined so that one surface is a continuous surface, It is formed asymmetrically in the thickness direction of the substrate A displacement control device, at least two independent Membrane type Piezoelectric / electrostrictive element It is formed on one side or both sides of the diaphragm, Distributed to both of the diaphragms, When the longitudinal direction of the connecting plate is the Y axis, the direction connecting the two diaphragms sandwiching the connecting plate is the X axis, and the thickness direction of the substrate is the Z axis, the connecting plate is displaced by the X axis. Axial displacement position orthogonal to position is multivalued Displacement control device characterized by being driven to draw a hysteresis-like displacement locus is provided.
In this displacement control device, a structure in which a fixed plate is joined to one end of the connecting plate is also preferable.
[0009]
Further, according to the present invention, there is provided a connecting plate having one end in the longitudinal direction sandwiched between at least two diaphragms and the other end sandwiched between at least two other diaphragms. Of a substrate having a concavity facing and forming a continuous surface connecting one side of each concavity, opposite Concerned Between the bottoms of the recesses Provided to straddle The diaphragm is also joined to at least the side surface of the recess, and the fixed plate is joined to the connecting plate so that the longitudinal direction of the fixed plate is parallel to the direction in which the diaphragm sandwiches the connecting plate. The thickness of the diaphragm is thinner than the thickness of each of the connecting plate, the fixed plate, and the substrate, and each surface of the diaphragm, the connecting plate, the fixed plate, and the substrate is a continuous surface. And are formed asymmetrically in the thickness direction of the substrate. A displacement control device, at least two independent Membrane type Piezoelectric / electrostrictive element It is formed on one side or both sides of the diaphragm, At least two diaphragms sandwiching the connecting plate at one end of the connecting plate, When the longitudinal direction of the connecting plate is the Y axis, the direction connecting the two diaphragms sandwiching the connecting plate (the longitudinal direction of the fixed plate) is the X axis, and the thickness direction of the substrate is the Z axis, The axial displacement position of the fixed plate orthogonal to the Y-axis displacement position is multivalued. Displacement control device characterized by being driven to draw a hysteresis-like displacement locus is provided.
[0010]
In the displacement control device having such a fixed plate as an essential component, it is also preferable to form a notch at the joint between the fixed plate and the connecting plate. In addition, it is also preferable that the connecting plate is divided into at least two in the longitudinal direction of the fixing plate and the fixing plate is joined to at least two connecting plates formed by being divided. In addition, it is also preferable to provide an elbow part in a fixed plate from the junction part of a fixed plate and a connection plate to the longitudinal direction of a fixed plate.
[0011]
In all the displacement control devices described above, it is preferable that at least the coupling plate and the diaphragm are joined to each other on the side surfaces, and at least the coupling plate, the diaphragm and the substrate are formed integrally. Is preferred. Of course, when the fixing plate is provided, the fixing plate can also be integrally formed. Such integral formation can be produced using a green sheet lamination method.
[0012]
In the displacement control device of the present invention, it is also preferable to dispose a piezoelectric / electrostrictive element used as one or more auxiliary elements in addition to the piezoelectric / electrostrictive element used for driving. In this case, the driving piezoelectric / electrostrictive element and the auxiliary element are not necessarily the same type. In addition, it is preferable to improve the durability by covering the piezoelectric / electrostrictive element and the electrode lead conducting to the electrode of the piezoelectric / electrostrictive element with an insulating layer made of resin or glass. At this time, a fluororesin or a silicone resin is preferably used as the resin. Furthermore, it is also preferable to form a shield layer made of a conductive member on the surface of the insulating layer, which contributes to improvement and stability of driving characteristics.
[0013]
Fully stabilized zirconia or partially stabilized zirconia is preferably used as the material for the substrate, connecting plate, and diaphragm. In addition, it is preferable that the shape of at least one of the fixed plate, the connecting plate, and the diaphragm is adjusted by trimming by laser processing or machining. Furthermore, it is also preferable to adjust the effective electrode area of the piezoelectric element by laser processing or machining the electrode in the piezoelectric element.
[0014]
Next, in the present invention, an actuator using the above-described displacement control device is provided. That is, the connecting plate or the fixing plate is driven by driving two or more independent piezoelectric / electrostrictive elements. The axial displacement position orthogonal to the X-axis displacement position or the Y-axis displacement position is multivalued. Driven to draw a hysteresis-like displacement trajectory Mentioned above An actuator using a plurality of displacement control devices, wherein the fixed plates are arranged so that the center lines of the fixed plates are substantially parallel, and / or the connecting plates are An actuator characterized by being arranged so as to be substantially parallel is provided.
[0015]
In addition, according to the present invention, the connecting plate or the fixing plate is driven by driving two or more independent piezoelectric / electrostrictive elements. The axial displacement position orthogonal to the X-axis displacement position or the Y-axis displacement position is multivalued. Driven to draw a hysteresis-like displacement trajectory Mentioned above An actuator using a plurality of displacement control devices, wherein the displacement control devices are provided around the displacement control device, is also provided.
Here, the plurality of displacement control devices intersect the front ends of the fixed plate or the connecting plate so that the center lines of the fixed plate intersect each other or so that the center lines of the connecting plate intersect each other. It is preferable to have a structure arranged toward the point.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a displacement control device (hereinafter simply referred to as “device”) of the present invention and an actuator using the device will be described below with reference to the drawings. As will be apparent from the following description, the device according to the present invention is a device in which a connecting plate or a fixed plate, which is a component, moves so as to draw a hysteresis-like displacement locus by driving a piezoelectric / electrostrictive element. However, the meaning of this “hysteresis-like” will be explained later. In addition, the actuator according to the present invention refers to a device group including a plurality of displacement control devices as components, and is not necessarily limited to the case where the actuator moves other objects, but the actuator itself is free-running, rotating, or the like. Including those that perform.
[0017]
1A is a plan view of the device 36, and FIG. 1B is a cross-sectional view including the X axis in the plan view and perpendicular to the plan view (paper surface) (hereinafter, such a cross-sectional view). Is expressed as “a cross-sectional view along the X-axis”).
[0018]
In the device 36, the connecting plate 2 is sandwiched between two diaphragms 3A and 3B (this clamping direction, that is, the joining direction of the connecting plate 2 and the diaphragms 3A and 3B is referred to as “X-axis direction”, and so on. In addition, the connecting plate 2 is bonded to the bottom surface of the recess 6 formed in the substrate 5, and the diaphragms 3 </ b> A and 3 </ b> B are bonded to the side surface and the bottom surface of the recess 6. Here, the joining direction of the connecting plate 2 and the substrate 5 is preferably a direction orthogonal to the X axis, and this direction is hereinafter defined as a “Y axis direction”. Independent piezoelectric / electrostrictive elements (hereinafter referred to as “piezoelectric elements”) 4A and 4B are arranged on one main plane of the diaphragms 3A and 3B, respectively.
[0019]
In the device 36, the diaphragms 3 </ b> A and 3 </ b> B need to be joined to at least the side surface of the recess 6, but need not necessarily be joined to the bottom surface of the recess 6. That is, the diaphragms 3 </ b> A and 3 </ b> B may be formed so as to extend between the connecting plate 2 and the side surface of the recess 6.
[0020]
In the piezoelectric elements 4A and 4B, electrode leads are arranged from the electrodes forming the piezoelectric elements 4A and 4B toward the substrate 5, but are omitted in each drawing of FIG. The term “independent piezoelectric element” is used not only to indicate that the piezoelectric element itself is a separate body, but also to mean that each piezoelectric element can be driven independently.
[0021]
The members of the connecting plate 2, the diaphragm 3, and the substrate 5 are preferably joined on the side surfaces of the members and formed integrally. If a green sheet lamination method described later is used, the device 36 that is integrally formed can be easily obtained. Although the connecting plate 2 is formed thicker than the diaphragm 3, it may be formed as thin as the diaphragm 3.
[0022]
Here, the connecting plate refers to an element that transmits displacement or vibration of the diaphragm caused by driving of the piezoelectric element and expands the displacement of the diaphragm. A fixed plate can be joined to the tip of the connecting plate so that the tip has an arbitrary shape. In other words, the connecting plate serves to connect the fixing plate and the substrate to each other and to displace or vibrate the fixing plate and the like. In the device 36, the connecting plate 2 itself also serves as the fixing plate. Can think.
[0023]
The diaphragm is an element that converts the distortion of the piezoelectric element disposed on the main plane (surface) into a bending mode displacement or vibration and transmits the displacement or vibration to the connecting plate. On the contrary, the diaphragm also plays a role of transmitting strain generated when the connecting plate or the fixed plate joined to the connecting plate is displaced or vibrated to the piezoelectric element. The substrate holds a movable part (including a fixed plate and the like when a connecting plate, a vibration plate, a piezoelectric element, and a fixed plate are provided) and is attached to a driving device or a measuring device. Various electrode terminals are provided, and elements used for handling in actual use.
[0024]
As described above, the substrate 5 is provided with the recess 6 for holding the connecting plate 2 and the diaphragms 3A and 3B in the predetermined form shown in FIG. The vertical surface) and the bottom surface (the surface perpendicular to the Y axis) are not necessarily perpendicular to each other, and the intersection of the side surface and the bottom surface may have a curvature. Such a recess 6 may be formed by cutting out a part of the outer peripheral side surface of the substrate 5, and uses three side surfaces among the four side surfaces when a rectangular hole is formed inside the substrate 5. It may be.
[0025]
Accordingly, the recess 6 does not necessarily have to be opened to one side in the Y-axis direction from which the connecting plate 2 protrudes. In this case, however, the displacement locus of the connecting plate 2 used in the device 36 will be described later. It is necessary to set the shape so as not to have an adverse effect.
[0026]
As a form of the piezoelectric elements 4A and 4B, as shown in FIG. 2, a piezoelectric element 88 in which a piezoelectric film 86 is sandwiched between a first electrode 85 and a second electrode 87 on a diaphragm 89 and formed in layers. As shown in FIG. 3, a piezoelectric film 90 is disposed on a diaphragm 89 as shown in FIG. 3, and the first electrode 91 and the second electrode 92 form a gap 93 having a constant width on the piezoelectric film 90. A piezoelectric element 94A having a comb-shaped structure can also be used. Note that the first electrode 91 and the second electrode 92 in FIG. 3 may be formed between the connection surfaces of the diaphragm 89 and the piezoelectric film 90. Furthermore, as shown in FIG. 4, a piezoelectric element 94B in which a piezoelectric film 90 is embedded between a comb-shaped first electrode 91 and a second electrode 92 is also preferably used. In the piezoelectric element 88, the lateral effect of the electric field induced strain (d ₃₁ ) In the piezoelectric elements 94A and 94B (d) ₃₃ ) Is preferably used.
[0027]
When the piezoelectric elements 94A and 94B having comb-shaped electrodes shown in FIGS. 3 and 4 are used, the amount of distortion can be increased by reducing the pitch W in the comb-shaped electrodes. Such piezoelectric elements shown in FIGS. 2 to 4 can be applied to all the devices of the present invention described later. Thus, when a voltage is applied to the piezoelectric elements 4A and 4B having various forms such as the piezoelectric element 88, a distortion corresponding to the applied voltage is generated in the piezoelectric film, and this distortion is transmitted to the diaphragm 3, and then the connecting plate. As a result, the connecting plate 2 undergoes a predetermined displacement.
[0028]
Here, as the piezoelectric elements 4A and 4B of the device 36, both d ₃₁ Assuming that a piezoelectric element of the type utilizing the above is disposed, the process of displacement of the connecting plate 2 due to the strain generated in the piezoelectric elements 4A and 4B will be considered. The voltages applied to the piezoelectric elements 4A and 4B are VA and VB, respectively, and the axis orthogonal to both the X and Y axes is the Z axis.
[0029]
5A to 5C are cross-sectional views in the ZX plane corresponding to FIG. 1B, and are explanatory views showing a transition of displacement of the connecting plate 2. FIG. 5D is also an explanatory diagram showing a change in the position of the front end surface 2F of the connecting plate 2 on the ZX plane. First, when a voltage is applied only to the piezoelectric element 4A without driving the piezoelectric element 4B, an electric field induced strain occurs in the piezoelectric film, and the piezoelectric element 4A contracts in the X-axis direction. In this way, as shown in FIG. 5A, the vibration plate 3A is displaced in the bending mode in the Z-axis direction perpendicular to the main plane of the vibration plate 3A represented by the arrow C. At this time, a force in the direction opposite to the arrow C indicated by the arrow D acts on the joint B1 between the diaphragm 3A and the connecting plate 2. The direction of the arrow D is the Z-axis direction and is orthogonal to the X-axis direction, and therefore does not include a component that displaces the connecting plate 2 in the X-axis direction. 2 is not displaced in the X-axis direction.
[0030]
However, when the vibration plate 3A is bent, the force acting on the joint B1 is not in the direction of the arrow D, but in the direction of the arrow E shown in FIG. E _A ) Will occur. Thus, the arrow E _A It is considered that the connecting plate 2 is displaced in the X-axis direction (rightward in the drawing) due to the displacement component. On the other hand, three sides of the diaphragm 3A are joined to the substrate 5 and the connecting plate 2, and one side is a free end. For this reason, as the bending displacement of the diaphragm 3A increases, the free end of the diaphragm 3A is displaced in the direction of arrow D, that is, in the Z-axis direction (upward in the drawing), and due to the displacement of the diaphragm 3A in the Z-axis direction. The connecting plate 2 is also displaced in the Z-axis direction.
[0031]
That is, when the position of the front end surface 2F of the connecting plate 2 in a state where no driving voltage is applied to the piezoelectric elements 4A and 4B is the point P in FIG. 5D, the front end of the connecting plate 2 is driven only by the piezoelectric element 4A. The surface 2F is displaced so as to move from the point P to the point Q. Therefore, at the point Q, the voltage applied to the piezoelectric element 4A is VA, and the voltage applied to the piezoelectric element 4B is 0 (zero). Such a state of voltage application is hereinafter referred to as (VA · 0).
[0032]
Contrary to the case described above, when a voltage is applied only to the piezoelectric element 4B without applying a voltage to the piezoelectric element 4A, the joint portion between the connecting plate 2 and the diaphragm 3B is driven by the piezoelectric element 4B. The force represented by the arrow F acting on B2 is the force represented by the arrow E when only the piezoelectric element 4A shown in FIG. 5 (b) is driven as shown in FIG. 5 (c). Is a direction symmetric about the Z axis. That is, by driving only the piezoelectric element 4B, the front end face F of the connecting plate 2 is displaced so as to move from the point P to the point S in FIG. The voltage application state at this point S is represented by (0 · VB).
[0033]
Accordingly, when a voltage is applied to the piezoelectric element 4B in a state in which the voltage application to the piezoelectric element 4A is maintained from the state where the front end surface 2F of the connecting plate 2 is at the point Q, the displacement component in the X-axis direction is canceled and reduced. However, since the displacement component in the Z-axis direction is added, the displacement amount in the X-axis direction is 0 in the state of the predetermined voltage (VA · VB), and the movement is made to the point R that is most displaced in the Z-axis direction be able to.
[0034]
In this way, by changing the voltage application state of the two independent piezoelectric elements 4A and 4B, the connecting plate 2 has a hysteresis in which the front end surface 2F is changed from P point → Q point → R point → S point → P point. It is possible to drive so as to draw a similar displacement locus, and of course, it is also possible to drive by reversing such a path. Furthermore, when the voltage applied to the piezoelectric elements 4A and 4B is (VA / 2 · VB / 2), the connecting plate 2 can be displaced to the T point. Therefore, it is possible to drive the connecting plate 2 along a path from the point P → the point Q → the point T → the point S → the point P. In this case, between the point Q and the point S, the Z-axis direction can be driven. The driving form is such that the displacement amount does not change relatively.
[0035]
In other words, in a structure in which the connecting plate is sandwiched between the two diaphragms 3A and 3B, at least two independent piezoelectric elements 4A and 4B are driven to be surrounded by the points P, Q, R, and S. In the range, the connecting plate 2 can be driven to draw a hysteresis-like displacement trajectory along an arbitrary path. In FIG. 5D, the displacement trajectory between points P to T is shown as a straight line, but as described above, the voltage applied to each of the piezoelectric elements 4A and 4B is adjusted. Of course, it is also possible to draw a locus so as to have a curved shape or a substantially circular shape.
[0036]
Thus, for example, as shown in FIG. 6, when the object 101 is placed on the XY plane of the connecting plate 2 and the tip surface 2F of the connecting plate 2 is driven to rotate counterclockwise, at least the connecting plate 2 The object 101 can be moved in the negative direction of the X axis (the direction of the arrow FF) by the friction between the object 101 and the object 101. In the connecting plate 2, the portion where the connecting plate 2 comes into contact with the object 101 may have a circular cross section instead of a rectangular cross section as shown in FIG. 6. That is, the shape of the connecting plate 2 is not limited to a rectangular shape. The above is d as a piezoelectric element. ₃₁ In the case of using an element of a type using ₃₃ Similarly, it is possible to drive so as to draw a hysteresis-like displacement locus in the case of an element of a type using the above.
[0037]
In the present invention, the term “hysteresis-like displacement locus” is used as the displacement form of the connecting plate 2, and this is used as the following meaning. In general, hysteresis refers to a phenomenon in which when another amount B changes with a change in a certain amount A, the value of B for the same A varies depending on the path of the change in A. If the displacement position, B is replaced with the Z-axis displacement position of the connecting plate 2, normally, when a voltage is applied to the piezoelectric element 4A, for example, when the voltage is changed from 0 to VA, the X-axis displacement position of the connecting plate 2 And the change in the Z-axis displacement position are indicated by a path from point P to point Q in FIG. In this case, the Z-axis displacement position with respect to the X-axis displacement position of the connecting plate 2 is uniquely determined.
[0038]
However, in the present invention, the connection plate 2 can be driven to take a path from the Q point to the R point by applying a voltage to the piezoelectric element 4B. Therefore, the Z-axis displacement position is different from the X-axis displacement position of the same connecting plate 2, and the Z-axis displacement position is not uniquely determined with respect to the X-axis displacement position. The path that is displaced from the point Q → the point R → the point S → the point P is an example of the displacement path (trajectory) of this device. It uses words and phrases. Therefore, the reciprocal displacement (Z-axis direction vibration) between the point P and the point R is an example in which the Z-axis displacement position is multivalued with respect to the X-axis displacement position of the connecting plate 2, and this is also a hysteresis-like state. It can be expressed as a displacement trajectory.
[0039]
Note that the voltage actually applied to the piezoelectric element for driving the device of the present invention to draw a hysteresis-like displacement locus as described above is the structure of the piezoelectric element, the piezoelectric characteristics of the piezoelectric film, and one device. It is necessary to adjust so that a suitable hysteresis-like displacement trajectory is drawn depending on the dimensional variation of each piezoelectric element.
[0040]
Now, in the device 36 described above, since the connecting plate 2 is sandwiched between the plurality of diaphragms, the torsional displacement around the Y axis is suppressed. In this case, the displacement in the Z-axis direction is also suppressed, but the displacement amount in the X-axis direction is increased. Further, when the diaphragms 3A and 3B are not joined to the bottom surface of the recess 6, twisting displacement around the Y axis is likely to occur, but the displacement in the Z axis direction can be increased. Furthermore, as will be described later, the shape of the hysteresis-like displacement trajectory can also be controlled by the shape of the connecting plate 2. As described above, the shape of the hysteresis-like displacement locus can be changed by a method for controlling the voltage applied to the piezoelectric element, but can also be changed by the structural design of the device itself.
[0041]
Now, similarly to the device 36, embodiments of the device that can be driven so as to draw the above-described hysteresis-like displacement locus will be described below. The device 37 shown in the plan view of FIG. 7A and the cross-sectional view (b) along the X-axis in the plan view has independent piezoelectric elements (4A. 4C) and (4B and 4D) are provided. Here, as the piezoelectric elements 4A to 4D, d ₃₁ Of the type using ₃₃ By appropriately selecting and arranging the type using the above and driving the piezoelectric elements 4A to 4D according to the driving principle shown in FIG. 5, it is possible to drive using all of the piezoelectric elements 4A to 4D. is there. For example, d ₃₁ In order to further increase the distortion of the diaphragm 3A caused by driving the piezoelectric element 4A using ₃₃ There is a mode in which the piezoelectric element 4C utilizing the above is driven.
[0042]
On the other hand, in the device 37, similarly to the device 36, the piezoelectric elements 4A and 4B can be used as driving elements, and the piezoelectric elements 4C and 4D can be used as auxiliary elements. Here, the auxiliary element refers to a failure diagnosis element, a displacement confirmation / judgment element, a driving auxiliary element, and the like. By using the auxiliary element, it is possible to drive the connecting plate with high accuracy. In addition, it is also preferable to arrange a plurality of auxiliary elements for different uses.
[0043]
The plan view of FIG. 8 shows a device 38 in which the fixing plate 1 is joined to the tip of the connecting plate 2 of the device 36. Here, the fixed plate is an element that further expands the displacement of the connecting plate and displaces it by a predetermined amount. For example, when moving an object that is difficult to contact with the rod-like member such as the connecting plate 2 shown in the figure. Furthermore, it is designed according to the shape of the object.
[0044]
In the device 38, two independent piezoelectric elements 4A and 4C divided in the Y-axis direction are formed on one main plane of one diaphragm 3A, and the other diaphragm 3B has the same configuration. Piezoelectric elements 4B and 4D are formed. In this case, it is preferable to use the piezoelectric elements 4A and 4B closer to the fixed plate 1 as drive elements and the piezoelectric elements 4C and 4D on the bottom surface side of the recess 6 as auxiliary elements. Piezoelectric elements are divided by a method of dividing the piezoelectric elements 4A and 4B by laser processing, which will be described later, or two elements as a set from the beginning when the piezoelectric elements 4A to 4D are arranged. Any of the methods may be used. Such divided formation and use method of the piezoelectric element can be applied to all the devices of the present invention.
[0045]
Next, FIG. 9A shows a plan view of the device 39, and FIG. 9B shows a cross-sectional view along the X1 axis in the plan view. In the device 39, the connecting plate 2 having one end in the longitudinal direction (Y-axis direction) sandwiched between the diaphragms 3A and 3B and the other end sandwiched between the other two diaphragms 3C and 3D is attached to the substrate 5. While straddling between the bottom surfaces of the formed recesses 6A and 6B facing each other, the diaphragms 3A to 3D are joined to the bottom surfaces and side surfaces of the recesses 6A and 6B, and the fixing plate 1 vibrates in the longitudinal direction of the fixing plate 1. The plates (3A, 3B), (3C, 3D) are joined to the connecting plate 2 so as to be parallel to the direction (X-axis direction) for sandwiching the connecting plate 2.
[0046]
For each of the diaphragms 3A to 3D, independent piezoelectric elements 4A to 4D are arranged on the main plane, but like the device 37 described above, the piezoelectric elements are arranged on both main planes of the diaphragms 3A to 3D. It can also be set up. Further, as is apparent from the drive mode of the device 39 described later, the piezoelectric elements 4A and 4B can be disposed only on the vibration plates 3A and 3B that sandwich the connecting plate 2 at one end of the connecting plate 2, respectively. However, when driven by two independent piezoelectric elements in this way, compared to the case where four independent piezoelectric elements 4A to 4D are disposed and driven on each of the diaphragms 3A to 3D, This is inferior in terms of displacement expansion efficiency.
[0047]
Instead of the diaphragm 3A, a set of two diaphragms each having a flat plate surface facing each other in parallel is used. Similarly, the diaphragm 3B is also composed of a pair of diaphragms, for a total of four sheets. The connecting plate may be sandwiched between the diaphragms. The same applies to the diaphragms 3C and 3D.
[0048]
Since the arrangement form of the piezoelectric elements 4A and 4B and the piezoelectric elements 4C and 4D in the device 39 is the same as that of the piezoelectric elements 4A and 4B in the device 36 described above, in the device 39, all of the piezoelectric elements 4A to 4D are arranged. d ₃₁ Or a piezoelectric element of a type using ₃₃ It is preferable to use a piezoelectric element of a type that utilizes
[0049]
For example, as the piezoelectric elements 4A to 4D, d ₃₁ When a voltage is applied only to the piezoelectric elements 4A and 4C, a force that causes the piezoelectric element 4A to displace the connecting plate 2 in the X-axis direction and a piezoelectric element 4C are used. However, the forces that try to displace the connecting plate 2 in the X-axis direction are opposite to each other. Therefore, at the junction between the fixed plate 1 and the connecting plate 2, the vicinity of the intersection of the X-axis and the Y-axis is the center. A force for rotating the connecting plate 2 mainly in the XY plane is generated. By this force, the fixed plate 1 is displaced so that the front end of the fixed plate 1 is driven in the Y-axis direction around the vicinity of the intersection of the X axis and the Y axis.
[0050]
That is, in the device 39, the bending displacement of the piezoelectric elements 4A and 4C causes the bending displacement of the connecting plate 2 in the X-axis direction, and the bending displacement of the connecting plate 2 is converted into the rotational displacement of the fixed plate 1 in the Y-axis direction. In this case, the amount of displacement can be increased by designing the length of the fixed plate 1 in the X-axis direction. The displacement in the Z-axis direction generated in the connecting plate 2 is also transmitted to the fixed plate 1.
[0051]
Similarly, when a voltage is applied only to the piezoelectric elements 4B and 4D, it is displaced in the opposite direction even in the Y-axis direction as compared with the case where the piezoelectric elements 4A and 4C are driven.
[0052]
In this way, the piezoelectric elements 4A and 4B in the device 39 are driven so that the connecting plate 2 draws a hysteresis-like displacement locus, and the voltage application state is made the same as the piezoelectric elements 4A and 4B in the device 36 described above. When the movement of the front end surface of the fixing plate 1 is represented on the YZ plane by combining the piezoelectric elements 4A and 4C of the pair and simultaneously combining the piezoelectric elements 4B and 4D of the other group, FIG. It can be driven to draw a similar hysteresis-like displacement locus.
[0053]
Note that the notch 9 formed at the joint between the connecting plate 2 and the fixed plate 1 of the device 39 effectively expands the X-axis direction displacement of the connecting plate 2 to the Y-axis direction displacement of the fixed plate 1 described above. The notch 9 is preferably formed so that the distance in the width direction of the connecting plate 2, that is, the distance in the X-axis direction is long before reaching the inside of the fixed plate 1, while the notch 11 It is preferable that the width of the notch 9, that is, the distance in the Y-axis direction of the notch 9 is short.
[0054]
Next, the device 40 shown in FIG. 10 divides the connecting plate 2 into two in the longitudinal direction (X-axis direction) of the fixed plate 1, and each of the divided connecting plates 2 extends in the straddling direction of the connecting plate 2. It has a form divided into two (in the Y-axis direction). Therefore, the fixed plate 1 is joined to the one-side main plane of the connecting plate 2 so as to be horizontally mounted on the four connecting plates 2 as a result. Here, it goes without saying that the connecting plate 2 and the fixing plate 1 may be integrally formed, and the connecting plate 2 may be divided into three or more parts. In the present invention, the division of the connecting plate in the longitudinal direction (X-axis direction) of the fixed plate is the width in the X-axis direction of the newly formed connecting plate as a result of dividing the connecting plate to form a gap. In addition to a case where the width of the connecting plate becomes smaller, the case where the connecting plate has a shape arranged in parallel with a gap in the X-axis direction without changing the width in the X-axis direction is also included.
[0055]
In the device 40, each of the piezoelectric elements 4A to 4D is configured to drive one connecting plate 2 via the corresponding vibration plates 3A to 3D, so that the distortion of the piezoelectric elements 4A to 4D is reduced. A plurality of points (joining portions) to be applied to the fixing plate 1 can be taken, and the fixing plate 1 can be efficiently driven by driving in the same manner as the device 39.
[0056]
In the gap portion 10, a plate-like member having a thickness smaller than that of the connecting plate 2 may be provided between the connecting plates 2 in the X-axis direction. In this case, the relative displacement amount of the fixed plate 1 is reduced as compared with the case where no plate member is straddled, but the rigidity can be increased and the fixed plate 1 can be operated at a faster response speed. It becomes. Further, the gap portion 10 does not necessarily have to be formed over the entire length (Y-axis direction length) of the connecting plate 2, and the effect can be obtained even in a partial range.
[0057]
In FIG. 11, the fixing plate 1 is integrally joined to two connecting plates 2 formed by being divided in the longitudinal direction of the fixing plate 1, and from the joint portion between the fixing plate 1 and the connecting plate 2. A plan view of the device 41 in which the fixing plate 1 is provided with the hinge 11 and the notch 9 is formed at the joint between the fixing plate 1 and the connecting plate 2 is shown in the longitudinal direction of the fixing plate 1. Since the hinge portion 11 assists the displacement drive in the Y-axis direction of the distal end of the fixed plate 1, it can be more effectively obtained a large displacement amount by being formed together with the notch portion 9. Such a hinge 11 can also be formed in the devices 39 and 40 described above.
[0058]
Next, taking the device 36 described above as an example, the form of forming electrode leads from piezoelectric elements will be described. 12A, the electrode leads 21A to 21D are provided on the piezoelectric elements 4A and 4B disposed in the device 36, and the insulating layer 22 is provided on the piezoelectric elements 4A and 4B and the electrode leads 21A to 21D. 12 is a plan view showing an embodiment in which a shield layer 23 is formed so as to cover 22, and FIGS. 12B to 12D are cross-sectional views along the X1 axis in FIG. , Showing different forms.
[0059]
The insulating layer 22 effectively functions to improve the environmental resistance characteristics of the piezoelectric elements 4A and 4B. The shield layer 23 has a function of preventing malfunctions and noises in addition to ensuring good displacement accuracy by blocking electromagnetic waves from the outside when the device is driven at a high frequency.
[0060]
As a form of arrangement of the shield layer 23, as shown in FIG. 12B, in addition to a form in which the substrate 5 is sandwiched, a wiring on the substrate 5 as shown in FIG. Examples include a form in which only the part is enclosed, and a form in which the wiring part is shielded only on the upper side as shown in FIG. 12 (d). Among them, the entire wiring part as shown in FIGS. 12 (b) and 12 (c) is used. The form which shields is preferable. In FIG. 12A, the conduction of the shield layer 23 formed on each surface of the substrate 5 is ensured using the through holes 24 provided in the substrate 5, but the side surface of the substrate 5 is used. The lever may be connected. Details of materials suitably used for forming the insulating layer 22 and the shield layer 23 will be described together with the constituent materials of the device later.
[0061]
Next, materials used for the device of the present invention will be described. The substrate, the fixing plate, the connecting plate, and the vibration plate may be any insulator or dielectric that can be formed integrally with the piezoelectric element without using an adhesive, and ceramics are preferably used. Then, fully stabilized zirconia, partially stabilized zirconia, alumina, magnesia, and the like can be used. Of these, fully stabilized zirconia and partially stabilized zirconia are most preferably used because they have high mechanical strength, high toughness, and low reactivity with piezoelectric films and electrode materials even in thin plates. In the case where fully stabilized zirconia or partially stabilized zirconia is used as a material for these substrates and the like, it is preferable that at least the diaphragm contains an additive such as alumina or titania.
[0062]
In addition, when ceramics are used, the device can be integrally formed using the green sheet lamination method described later, so that the reliability of the joints at each part is ensured and the manufacturing process is simplified. To preferred.
[0063]
Note that the thickness and shape of the fixing plate in the device of the present invention are not limited and have been appropriately designed according to the intended use. However, the thickness of the substrate is also appropriately determined in consideration of operability, and is not necessarily limited. It need not be plate-shaped. On the other hand, the thickness of the diaphragm is preferably about 3 to 20 μm, and the combined thickness of the diaphragm and the piezoelectric element is preferably 15 to 60 μm. The connecting plate preferably has a thickness of 20 to 600 μm and a width of 30 to 500 μm, and the connecting plate has an aspect ratio (width (length in the X-axis direction) / thickness direction (Z-axis direction) length) of 0. The range of 1 to 15 is preferable, but in order to make the displacement in the XY plane more dominant, the range of 0.1 to 7 is preferable.
[0064]
As the piezoelectric film in the piezoelectric element, piezoelectric ceramics formed into a film shape are preferably used, but electrostrictive ceramics, ferroelectric ceramics, or antiferroelectric ceramics can also be used. Moreover, any of materials that require polarization treatment and materials that do not need to be used may be used. However, when used for a magnetic recording head or the like, since the linearity between the displacement of the fixed plate and the drive voltage or output voltage is important, it is preferable to use a material having a small distortion history. It is preferable to use a material of 10 kV / mm or less.
[0065]
Specific piezoelectric ceramics include lead zirconate, lead titanate, lead magnesium niobate, lead nickel niobate, lead zinc niobate, lead manganese niobate, lead antimony stannate, lead manganese tungstate, lead cobalt niobate , Magnesium tantalate, barium titanate, etc., and ceramics containing any combination of these. Among these, in the present invention, a material mainly composed of components composed of lead zirconate, lead titanate and lead magnesium niobate is preferably used. This is because such a material has a high electromechanical coupling coefficient. The reason is that it has a piezoelectric constant, has low reactivity with the substrate (ceramic substrate) during sintering of the piezoelectric film, and can stably form a substrate having a predetermined composition.
[0066]
Furthermore, the piezoelectric ceramics such as lanthanum, calcium, strontium, molybdenum, tungsten, barium, niobium, zinc, nickel, manganese, cerium, cadmium, chromium, cobalt, antimony, iron, yttrium, tantalum, lithium, bismuth, tin, etc. You may use the ceramic which added the oxide or the combination of these, or another compound suitably. For example, it is also preferable to use lead zirconate, lead titanate, and lead magnesium niobate as main components, and to contain lanthanum or strontium to adjust the electric field and piezoelectric characteristics.
[0067]
On the other hand, the electrode of the piezoelectric element is preferably made of a metal that is solid at room temperature and has excellent conductivity. For example, aluminum, titanium, chromium, iron, cobalt, nickel, copper, zinc, niobium, molybdenum , Ruthenium, palladium, rhodium, silver, tin, tantalum, tungsten, iridium, platinum, gold, lead, etc., or a combination of any of these metals, and the same as the piezoelectric film or diaphragm A cermet material in which the material is dispersed may be used.
[0068]
The material selection of the electrode in the piezoelectric element is determined depending on the method of forming the piezoelectric film. For example, when a piezoelectric film is formed on the first electrode by firing after the first electrode is formed on the diaphragm, the first electrode has a high melting point metal such as platinum that does not change even at the firing temperature of the piezoelectric film. However, since the second electrode formed on the piezoelectric film after forming the piezoelectric film can be formed at a low temperature, a low melting point metal such as aluminum can be used.
[0069]
In addition, the piezoelectric element can be formed by integral firing. In this case, both the first electrode and the second electrode must be made of a refractory metal that can withstand the firing temperature of the piezoelectric film. On the other hand, when the first and second electrodes 91 and 92 are formed on the piezoelectric film 90 as in the piezoelectric element 94A shown in FIG. 3, both can be formed using the same low melting point metal. As described above, the first electrode and the second electrode may be appropriately selected depending on the formation temperature of the piezoelectric film represented by the firing temperature of the piezoelectric film and the structure of the piezoelectric element. The electrode lead can be formed simultaneously with the electrode in the piezoelectric element, and the electrode lead on the diaphragm is formed simultaneously with the piezoelectric element, and then the electrode lead on the substrate is formed by sputtering, You may form using various methods, such as a screen printing method.
[0070]
Subsequently, an insulating glass or resin is used as the material of the insulating layer formed on the piezoelectric element and the electrode lead. In order to improve the performance of the device without hindering the displacement, a resin is used rather than glass. Fluorine resin excellent in chemical stability, for example, tetrafluoroethylene resin Teflon (Teflon PTFE manufactured by DuPont), tetrafluoroethylene / hexafluoropropylene copolymer resin system Teflon (Teflon FEP), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin-based Teflon (Teflon PFA), PTFE / PFA composite Teflon, etc. are preferably used.
[0071]
Moreover, although it is inferior to these fluororesins in corrosion resistance, a weather resistance, etc., a silicone resin (especially thermosetting silicone resin) is also used suitably, and an epoxy resin, an acrylic resin, etc. can also be used according to the objective. it can. It is also preferable to form the insulating layer using different materials for the piezoelectric element and its vicinity and the electrode lead and its vicinity. Furthermore, it is also preferable to add inorganic / organic fillers to the insulating resin to adjust the rigidity of the diaphragm and the like.
[0072]
When the insulating layer is formed, various materials such as gold, silver, copper, nickel, and aluminum are preferably used as the material for the shield layer formed on the insulating layer. All metal materials used for the electrodes and the like can be used. Alternatively, a conductive paste obtained by mixing metal powder with resin can also be used.
[0073]
Next, a method for manufacturing a device of the present invention will be described using the above-described device 39 as an example. Since the device of the present invention is composed of a plurality of members such as a connecting plate and a fixing plate, it can be produced by joining parts made of various materials prepared separately. However, in this case, the productivity is not high, and damage or the like is likely to occur at the joint portion, which causes a problem in terms of reliability. Therefore, in the present invention, a green sheet lamination method using ceramic powder as a raw material is suitably employed.
[0074]
In the green sheet laminating method, first, a ceramic powder such as zirconia, which is a material, is added and mixed with a binder, a solvent, a dispersant and the like to prepare a slurry, and after defoaming treatment, a reverse roll coater method, a doctor blade method A green sheet or green tape having a predetermined thickness is produced by a method such as the above. Next, various green sheet members (hereinafter referred to as “sheet members”) as shown in FIG. 13 are prepared by a method such as punching (punching) the green sheets using a mold.
[0075]
The sheet member 51 is a member that becomes the substrate 5, the connecting plate 2, the fixed plate 1, and the vibration plates 3 </ b> A to 3 </ b> D after firing, and at this time, the shape thereof is in a single plate. As described above, since the diaphragms 3A to 3D are preferably formed as thin as 3 to 20 μm, laser processing or the like is performed after firing rather than forming the shapes of these members in a green sheet state. Therefore, it is preferable to cut off unnecessary portions because the shape accuracy is kept good.
[0076]
The sheet member 52 is a member for forming the thickness of the fixed plate 1 and the connecting plate 2 to be thicker than the vibration plates 3A to 3D in addition to the substrate 5, and includes the reference hole 54, the window portion 55, the fixed plate 1, A connecting plate 2 is formed. A cutout portion 11 can be formed at the joint between the fixed plate 1 and the connecting plate 2. A predetermined number of the sheet members 52 are stacked to obtain a desired thickness of the fixing plate 1 and the connecting plate 2. When the fixing plate 1 is formed thinner than the connecting plate 2, a sheet member in which only the portion that becomes the fixing plate 1 is deleted from the sheet member 52 is produced and laminated. The sheet member 53 in which the reference hole 54 and the window portion 55 are formed is a member that becomes the substrate 5. A desired thickness can be obtained by laminating one or more predetermined sheets.
[0077]
These sheet members 51 to 53 are laminated in this order while positioning using the reference hole 54, and are integrated by a method such as thermocompression bonding to produce a laminated body. And after that, baking is performed at a temperature of 1200 ° C. to 1600 ° C. Here, piezoelectric elements 4A to 4D are formed in advance at positions where the vibration plates 3A to 3D of the sheet member 51 are finally formed, It is also preferable to fire integrally with the laminate.
[0078]
As a method for arranging the piezoelectric elements 4A to 4D by simultaneous firing of the laminate and the piezoelectric element, a piezoelectric film is formed by a press forming method using a die or a tape forming method using a slurry raw material. A method of laminating the piezoelectric film before firing on the sheet member 51 by thermocompression bonding and simultaneously sintering the substrate and the piezoelectric film is mentioned. However, in this case, it is necessary to previously form electrodes on the substrate or the piezoelectric film by using a film forming method described later.
[0079]
The firing temperature of the piezoelectric film is appropriately determined depending on the material constituting the piezoelectric film, but is generally 800 ° C. to 1400 ° C., preferably 1000 ° C. to 1400 ° C. In this case, in order to control the composition of the piezoelectric film, it is preferable to sinter by adjusting the atmosphere in the presence of an evaporation source for the material of the piezoelectric film. In particular, when using a substrate after firing, which will be described later, the atmosphere adjustment for relaxing the firing stress of the piezoelectric film and drawing out higher material properties is performed by observing the fired piezoelectric film with an electron microscope, etc. It is preferable to control by monitoring the distribution.
[0080]
For example, when a material containing lead zirconate is used, such as a material mainly composed of lead zirconate, lead titanate, and lead magnesium niobate, which are piezoelectric ceramics preferably used in the present invention. In this case, it is preferable to adjust the atmosphere so that the zirconium component is segregated in the fired piezoelectric film, and fire it. More preferably, the atmosphere should be such that segregation of the zirconium component is recognized on the surface of the piezoelectric film and almost no segregation is observed inside the piezoelectric film. A piezoelectric film having such a component distribution is superior in vibration characteristics compared to a piezoelectric film without segregation, that is, has a large vibration amplitude, and the firing stress is relaxed by segregation of the zirconium component. It has the characteristic that the inherent material properties are maintained without significantly deteriorating.
[0081]
Therefore, in the device of the present invention, it is most preferable to form the piezoelectric element so as to be such a piezoelectric film. In addition to the piezoelectric film composition, after the piezoelectric film is fired, each component of the device, for example, a connecting plate, a substrate, etc. contains a component of the piezoelectric material, particularly titanium oxide in the case of the piezoelectric material containing titanium oxide. It is also preferable to perform firing in the atmosphere. When the piezoelectric film and the substrate are simultaneously fired, it is necessary to match the firing conditions of the two.
[0082]
In addition, at the vibration plate forming position in the laminated body after sintering, a thick film forming method such as screen printing method, dipping method, coating method, electrophoresis method, ion beam method, sputtering method, vacuum deposition, ion plating method, Piezoelectric elements can be arranged by various thin film forming methods such as chemical vapor deposition (CVD) and plating. Among these, in the present invention, when forming the piezoelectric film, a thick film forming method such as a screen printing method, a dipping method, a coating method, or an electrophoresis method is preferably employed. This is because these methods use a paste, slurry, suspension, emulsion, sol, or the like mainly composed of piezoelectric ceramic particles having an average particle size of 0.01-5 μm, preferably 0.05-3 μm. This is because good piezoelectric actuation characteristics can be obtained. In particular, the electrophoresis method is capable of forming a film with high density and high shape accuracy, as well as technical documents “DENKI KAGAKA”, 53, No. 1 (1985) p63-68, written by Kazuo Anzai ”. Accordingly, it is preferable to select and use a method as appropriate in consideration of required accuracy, reliability, and the like.
[0083]
For example, after firing the manufactured laminate under predetermined conditions, the first electrode is printed and fired at a predetermined position on the surface of the fired sheet member 51, and then the piezoelectric film is printed and fired, and the second electrode is further fired. The piezoelectric element can be disposed by printing and firing, and then an electrode lead for connecting the electrode in the formed piezoelectric element to the measuring device is printed and fired. Here, for example, platinum (Pt) is used as the first electrode, lead zirconate titanate (PZT) is used as the piezoelectric film, gold (Au) is used as the second electrode, and silver (Ag) is used as the electrode lead. When the material is used, the firing temperature in the firing process is set so as to be successively lowered, so that in a certain firing stage, re-sintering of the material fired before that does not occur, and peeling and aggregation of the electrode material etc. It is possible to avoid the occurrence of defects.
[0084]
By selecting an appropriate material, each member of the piezoelectric element and the electrode lead can be sequentially printed and integrally fired at one time. On the other hand, after forming the piezoelectric film, each electrode or the like can be printed at a low temperature. Can also be provided. In addition, each member of the piezoelectric element and the electrode lead may be formed by a thin film method such as sputtering or vapor deposition, and in this case, heat treatment is not necessarily required.
[0085]
By forming the piezoelectric element by the film forming method in this way, the piezoelectric element and the diaphragm can be integrally bonded and arranged without using an adhesive, ensuring reliability and reproducibility and integration. Can be easy. Here, the piezoelectric film may be further formed into an appropriate pattern. Examples of the forming method include a screen printing method, a photolithography method, a laser processing method, or a mechanical processing method such as slicing or ultrasonic processing. Can be used.
[0086]
In this manner, a diaphragm, a fixing plate, a connecting plate, and a cutout portion as necessary are formed at predetermined positions of the fired laminate on which the piezoelectric elements and electrode leads are formed. Here, it is preferable to cut and remove unnecessary portions of the sintered sheet member 51 by processing using the fourth harmonic of the YAG laser. In this way, the device 39 having the diaphragms 3A to 3D, the fixed plate 1, and the connecting plate 2 having the shape shown in FIG. 9 is obtained. Note that a portion corresponding to the substrate 5 and an unnecessary portion may be removed by the laser processing or dicing.
[0087]
Further, the shape of the fixing plate 1 and the connecting plate 2 mainly formed by the sheet member 52 and the shape of the diaphragms 3A to 3D formed by the sheet member 51 are adjusted during such processing, thereby forming the shape. It is also preferable to adjust the amount of displacement and drive characteristics as well as to reduce the variation of the displacement.
[0088]
Further, as shown in FIG. 14, the piezoelectric element 88 shown in FIG. 2 has the second electrode 87 as the upper electrode and the first electrode 85 as the lower electrode, and the piezoelectric element 88 in which the piezoelectric film 86 is formed in the middle is once. After placement, the upper electrode is trimmed by YAG fourth harmonic laser, machining, etc. to adjust the effective electrode area of the piezoelectric element, and the electrical characteristics such as the impedance of the device are adjusted to obtain a predetermined displacement characteristic. It is also preferable. When the structure of the piezoelectric element 88 is a comb structure as shown in FIG. 3 or FIG. 4, a part of one or both electrodes may be trimmed.
[0089]
In such processing, in addition to the processing using the YAG fourth harmonic laser, the second or third harmonic of the YAG laser and the YAG laser, excimer laser, CO ₂ Various processing methods suitable for the size and shape of the device, such as laser processing using a laser, electron beam processing, dicing (machining), and the like can be applied.
[0090]
In addition, the device of the present invention can be manufactured using a pressure molding method using a molding die, a casting molding method, an injection molding method, or the like, in addition to the above-described manufacturing method using the green sheet. Also in these cases, before and after firing, machining is performed by machining such as cutting, grinding, laser machining, punching by punching, or ultrasonic machining to obtain a predetermined shape.
[0091]
The piezoelectric elements 4A to 4D and the insulating layers formed on the electrode leads in the device 39 thus manufactured can be formed by using a screen printing method, a coating method, a spray method, or the like using glass or resin. Here, when glass is used as the material, it is necessary to raise the temperature of the device itself to about the softening temperature of the glass, and since the hardness is large, there is a risk of inhibiting displacement or vibration, but the resin is soft, It is preferable to use a resin because it only requires a drying process.
[0092]
It has already been stated that fluororesins or silicone resins are preferably used as the resin used for the insulating layer. However, when these resins are used, they are used for the purpose of improving the adhesion with the underlying ceramic. It is preferable to form a primer layer according to the type of resin and ceramic to be formed, and form an insulating layer thereon.
[0093]
Next, since the shield layer formed on the insulating layer is difficult to be fired when the insulating layer is made of a resin, when various metal materials are used, a sputtering method or the like is used. On the other hand, when a conductive paste made of a metal powder and a resin is used, a screen printing method, a coating method, or the like can be suitably used. In the case where the insulating layer is formed of glass, the conductor paste can be screen printed or fired at a temperature or less at which the glass does not flow.
[0094]
As described above, the embodiment, the constituent material, and the manufacturing method of the displacement control device of the present invention have been described. According to the present invention, an actuator using the various devices described above is also provided. The actuator 61 shown in the plan view of FIG. 15 includes a plurality of (in the case of FIG. 15, a total of eight) devices 39 such that the center line (Y axis) of each fixing plate 1 is substantially parallel. Further, the XY plane of each fixing plate 1 has a structure arranged so as to form the same plane in a stationary state. And the conveyed product 69 is mounted so that the front-end | tip part of each fixing plate 1 may be contacted.
[0095]
In the actuator 61, devices 39, for example, devices 39 </ b> A and 39 </ b> E that are symmetric with respect to the ZX plane are arranged so that the tip of the fixed plate 1 draws a hysteresis-like displacement locus that is symmetric with respect to the ZX plane. When driven, a force that moves in the X-axis direction acts on the conveyed product 69 based on the principle shown in FIG. The direction in which the hysteresis-like displacement locus is drawn may be set depending on which direction in the X-axis direction the conveyed object 69 is moved. The actuators 61B to 39D are driven to draw a hysteresis-like displacement locus equivalent to the device 39A, and the devices 39F to 39H are driven to draw a hysteresis-like displacement locus equivalent to the device 39E. It can be used as a linear motor, a conveyor, or the like.
[0096]
The devices 39A to 39D are integrally formed on the substrate 5A, and the devices 39E to 39H are integrally formed on the substrate 5B. An actuator having such a structure can be easily manufactured by using the green sheet laminating method described above. Of course, the devices 39A to 39H are separately manufactured and arranged at predetermined positions. The actuator 61 may be configured. Needless to say, the device constituting the actuator 61 is not limited to the device 39.
[0097]
Next, in FIG. 16, eight devices 39 </ b> A to 39 </ b> H share one substrate 5 such that the front end of the fixing plate 1 faces the outside of the substrate 5 and the center of each fixing plate 1. The perspective view (a) of the actuator 62 arrange | positioned so that a line | wire (Y-axis) may become parallel, and sectional drawing (b) in the ZX plane which passes along line AA in a perspective view are shown.
[0098]
When the devices 39A to 39H are driven in the same manner as the actuator 61 described above, the actuator 62 can be used as a component that linearly travels. As shown in FIG. 16B, the actuator 62 is in a state where the substrate 5 is grounded and each fixing plate 1 is separated from the ground surface in a stationary state. By making the height difference h less than the displacement amount of the fixed plate 1 in the Z-axis direction, the height difference h works as a clutch. That is, when the amount of displacement of the fixed plate 1 in the Z-axis direction exceeds the height difference h, the actuator 62 can operate so as to move, but the displacement of the fixed plate 1 in the Z-axis direction. When the amount is less than or equal to the height difference h, the vehicle cannot run on its own.
[0099]
Next, FIG. 17A shows a plan view of an actuator 64 using two devices 36 (devices 36A and 36B) shown in FIG. FIG. 17B is a cross-sectional view along the Y axis in FIG. 17A. In FIG. 17B, the diaphragms 3A and 3B and the piezoelectric elements 4A and 4B in the devices 36A and 36B are shown. In order to clarify the position, the positions of these members that are not on the Y-axis are also shown.
[0100]
17 (a) and 17 (b), the X and Y axes are not provided for each of the devices 36A and 36B, an XYZ orthogonal coordinate system as shown is set, and the intersection of each axis is determined. The origin is O. At this time, the actuator 64 has a structure in which the devices 36A and 36B are arranged at positions that are point-symmetric with respect to the origin O, and the central portion of the actuator 64 is in contact with the fixed plates 1 of the devices 36A and 36B. A rotating body 68 whose center of rotation is determined by an axis 67 is disposed. Here, the rotation center of the shaft needle 67 and the point symmetry center (origin O) of the actuator are arranged to coincide.
[0101]
A predetermined signal (voltage) is applied to each of the devices 36A and 36B so that the connecting plate 2 of the devices 36A and 36B generates a reciprocating motion of the point P and the point R described in FIG. By adding to 36B, it can be set as the motor which rotates the rotary body 68 in a fixed direction. At this time, the contact between the connecting plate 2 and the rotating body 68 is performed at a predetermined angle so as to rotate in a certain direction. 17 (a) and 17 (b), it is composed of a set of devices at point-symmetrical positions, but another set of devices at point-symmetrical positions is further arranged so that each set If the contact angle between the rotating body 68 and each connecting plate 2 is opposite to each other, it is preferable not only to rotate in a fixed direction but also to rotate in both directions.
[0102]
On the other hand, the displacement form of the connecting plate 2 is driven from the above-described displacement in the Z-axis direction so that a rotation locus such as P point → Q point → R point → S point → P point in FIG. As a result, the rotary body 68 can be caused to rotate. In this case, since the direct rotational motion of the connecting plate 2 can be transmitted to the rotating body 68, high-speed rotation with high torque is possible compared to the case of rotating using the Z-axis direction displacement described above. In addition, it is preferable that the rotation direction can be set to both directions with only one set of devices by changing the drive signal.
[0103]
Next, FIG. 18A is a plan view of an actuator 63 formed by surrounding the device 39, and FIG. 18B shows a cross-sectional view along the X axis in the plan view. Here, in the actuator 63, the X axis and the Y axis are not set for the devices 39A to 39F, and the XYZ axes shown in FIG. 18A are defined in the actuator 63 itself.
[0104]
In the actuator 63, the center lines of the fixing plates 1 (lines indicating the length direction of the fixing plates) intersect with each other, and the tips of the fixing plates 1 intersect with the center lines (the X axis and the Y axis). The devices 39A to 39E are arranged so as to go to the intersections of the axes. A rotating body 68 whose rotation center is determined by an axis 67 is disposed at the center of the actuator 62 so as to contact each fixed plate 1.
[0105]
All of the devices 39A to 39E are driven so as to draw a hysteresis such that a force is transmitted from each fixing plate 1 in a direction in which the rotating body 68 is rotated in one direction, thereby causing the rotating body 68 to cause a rotational motion. It is possible. Further, by reversing the direction in which the fixed plate 1 draws the hysteresis, the rotation direction can be easily reversed at a high speed. Thus, the actuator 63 can be suitably used as a motor.
[0106]
It should be noted that the actuator 63 has an advantage that the torque can be further increased because more drive parts can be obtained compared to the actuator 64 described above. Further, like the actuator 64, it is of course possible to drive the rotating body 68 using a method using displacement in the Z-axis direction.
[0107]
By the way, like the actuator 62, the disk-shaped substrate is used so that the center line of the fixed plate intersects from the disk-shaped substrate, and the fixed plate of the fixed plate is crossed. For example, the device 39 can be used as an actuator that rotates by disposing the device 39 on the disk-shaped substrate so that the tip projects radially outward. In this case, it is preferable to provide the disk-shaped substrate with an axis for determining the center of rotation. Such a self-running rotary actuator is difficult to use as a rotary motor in consideration of a method of applying a voltage to a piezoelectric element, but can be sufficiently used as an actuator for controlling a minute angular displacement.
[0108]
The operation speed of the actuator according to the present invention described above can be easily achieved by controlling the frequency and voltage value of the voltage applied to the piezoelectric element, and has excellent characteristics in the operation performance of rest and inversion. .
[0109]
As described above, the embodiments of the displacement control device and the actuator using the same according to the present invention have been described in detail, but the present invention is not limited to these embodiments and does not depart from the spirit of the present invention. It should be understood that various changes, modifications, and improvements can be made based on the ordinary knowledge of those skilled in the art.
[0110]
【The invention's effect】
The displacement control device of the present invention has a simple structure, is easy to reduce in size and weight, has low power consumption and high displacement efficiency, and is hardly affected by harmful vibration from the outside. As a result, the displacement control device itself can be used as a sensor or an actuator itself, and an actuator composed of a plurality of displacement control devices can be used as a linear motor, a rotary motor, a position control actuator, etc. excellent in braking performance. it can. Further, by using a simple manufacturing method such as a green sheet laminating method with a wide allowable design range, there is an effect that it can be manufactured at a low cost while improving reliability as an integrated structure. Furthermore, there is an advantage that a material to be selected has a wide allowable range, and a material suitable for each purpose can be used.
[Brief description of the drawings]
1A and 1B are a plan view and a cross-sectional view showing an embodiment of a displacement control device of the present invention.
FIG. 2 is a perspective view showing an embodiment of a piezoelectric element disposed in the displacement control device of the present invention.
FIG. 3 is a perspective view showing another embodiment of a piezoelectric element disposed in the displacement control device of the present invention.
FIG. 4 is a perspective view showing still another embodiment of a piezoelectric element disposed in the displacement control device of the present invention.
FIG. 5 is an explanatory diagram of a drive mode of the displacement control device of the present invention.
FIG. 6 is a schematic diagram showing transmission of force to another object by driving the displacement control device of the present invention.
7A and 7B are a plan view and a cross-sectional view showing another embodiment of the displacement control device of the present invention.
FIG. 8 is a plan view showing still another embodiment of the displacement control device of the present invention.
FIG. 9 is a plan view (a) and a cross-sectional view (b) showing still another embodiment of the displacement control device of the present invention.
FIG. 10 is a plan view showing still another embodiment of the displacement control device of the present invention.
FIG. 11 is a plan view showing still another embodiment of the displacement control device of the present invention.
FIGS. 12A and 12B are a plan view and cross-sectional views (b) to (d) showing a protection form of electrodes and the like of the displacement control device of the present invention. FIGS.
FIG. 13 is a plan view showing an example of the shape of a sheet member used for manufacturing the displacement control device of the present invention.
FIG. 14 is an explanatory diagram showing an example of a method for processing a piezoelectric element in the displacement control device of the present invention.
FIG. 15 is a plan view showing an embodiment of an actuator using the displacement control device of the present invention.
FIG. 16 is a perspective view (a) and a sectional view (b) showing another embodiment of an actuator using the displacement control device of the present invention.
17A and 17B are a plan view and a cross-sectional view, respectively, showing another embodiment of an actuator using the displacement control device of the present invention.
18A and 18B are a plan view and a cross-sectional view showing still another embodiment of an actuator using the displacement control device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Fixed plate, 2 ... Connection plate, 2F ... Front end surface of connection plate, 3A-3D ... Vibration plate, 4A-4D ... Piezoelectric element, 5 * 5A * 5B ... Substrate, 6 * 6A * 6B ... Recess, 9 ... Notch part, 10 ... Gap part, 11 ... Hinge part, 21A-21D ... Electrode lead, 22 ... Insulating layer, 23 ... Shield layer, 36-41 ... Displacement control device, 36A / 36B, 39A-39H ... Displacement control device 51-53 ... sheet member, 54 ... reference hole, 55 ... window, 61-64 ... actuator, 67 ... axial core, 68 ... rotating body, 69 ... conveyed material, 85 ... first electrode, 86 ... piezoelectric film, 87 ... second electrode, 88 ... piezoelectric element, 89 ... diaphragm, 90 ... piezoelectric film, 91 ... first electrode, 92 ... second electrode, 93 ... gap portion, 94A / 94B ... piezoelectric element, 101 ... object.

Claims (12)

Nipped connecting plate by two diaphragms and with said connecting plate is joined to the bottom surface of the recess formed in the substrate, Ri the diaphragm Na joined to the side surface of at least the concave portion,
The thickness of the vibration plate is thinner than the thickness of each of the connection plate and the substrate, and the vibration plate, the connection plate, and the substrate are joined such that one surface thereof is a continuous surface, and the substrate A displacement control device formed asymmetrically in the thickness direction of
At least two independent film type piezoelectric / electrostrictive elements are formed on one side or both sides of the diaphragm , and are distributed and arranged on both of the diaphragms.
When the longitudinal direction of the connecting plate is the Y axis, the direction connecting the two diaphragms sandwiching the connecting plate is the X axis, and the thickness direction of the substrate is the Z axis, the connecting plate is displaced by the X axis. A displacement control device that is driven so as to draw a hysteresis-like displacement locus in which an axial displacement position orthogonal to the position is multivalued .   The displacement control device according to claim 1, wherein a fixed plate is joined to one end of the connecting plate. A connecting plate having one end in the longitudinal direction sandwiched between at least two diaphragms and the other end sandwiched between at least two other diaphragms has opposing recesses, and one side surface of each other recess the substrate forming a continuous surface formed by connecting, with is provided so as to straddle between the bottom surface of the recess facing, the diaphragm is bonded at least with the side surface of the recessed portion, the fixed plate in the longitudinal direction of the fixed plate Ri Na said diaphragm is joined to said connecting plate so as to be parallel to the direction sandwiching the connecting plate,
The thickness of the diaphragm is thinner than the thickness of each of the connecting plate, the fixed plate, and the substrate, and each surface of the diaphragm, the connecting plate, the fixed plate, and the substrate is a continuous surface. And a displacement control device formed asymmetrically in the thickness direction of the substrate ,
At least two independent film-type piezoelectric / electrostrictive elements are formed on one side or both sides of the diaphragm, and at least two sheets sandwiching the connecting plate at one end of the connecting plate. Arranged on both diaphragms,
When the longitudinal direction of the connecting plate is the Y axis, the direction connecting the two diaphragms sandwiching the connecting plate (the longitudinal direction of the fixed plate) is the X axis, and the thickness direction of the substrate is the Z axis, A displacement control device , wherein the fixed plate is driven so as to draw a hysteresis-like displacement trajectory in which the axial displacement position orthogonal to the Y-axis displacement position is multivalued . The notch part which formed the distance of the width direction of the said connection plate long in the junction part of the said fixation plate and the said connection plate until it reaches in the said fixed plate is characterized by the above-mentioned. Displacement control device. 5. The displacement according to claim 3, wherein the connecting plate is divided into two in the longitudinal direction of the fixing plate and the fixing plate is joined to at least two connecting plates formed by dividing the connecting plate. Control device. 6. The piezoelectric / electrostrictive element and an electrode lead conducting to the electrode of the piezoelectric / electrostrictive element are covered with an insulating layer made of resin or glass. The displacement control device described . The displacement control device according to claim 6, wherein the resin is a fluororesin or a silicone resin . The displacement control device according to claim 6 or 7, wherein a shield layer made of a conductive member is further formed on the surface of the insulating layer . The displacement control device according to any one of claims 1 to 8, wherein at least the substrate, the connecting plate, and the diaphragm are made of fully stabilized zirconia or partially stabilized zirconia . By driving the independent two or more piezoelectric / electrostrictive elements, connecting plates or fixed plates, axial displacement position of the multilevel and name Ru hysteresis-like perpendicular to the X axis displacement position or the Y-axis displacement position An actuator comprising a plurality of the displacement control devices according to any one of claims 1 to 9, which are driven so as to draw a displacement trajectory,
The fixing plates are arranged so that the center lines of the fixing plates are substantially parallel and / or the connecting plates are arranged so that the center lines of the connecting plates are substantially parallel. Characteristic actuator . By driving two or more independent piezoelectric / electrostrictive elements, the connecting plate or fixed plate is a hysteresis-like displacement in which the axial displacement position orthogonal to the X-axis displacement position or the Y-axis displacement position becomes multivalued. An actuator using a plurality of the displacement control devices according to any one of claims 1 to 9 driven so as to draw a trajectory,
An actuator characterized by surrounding the displacement control device . In the plurality of displacement control devices, the front ends of the fixed plate or the connecting plate intersect the center line so that the center lines of the fixed plate intersect with each other or the center lines of the connecting plate intersect with each other. The actuator according to claim 11, wherein the actuator is disposed toward the point to be operated .

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